Melatonin Implants

Melatonin implants (Dermatonin)have been used by several veterinary dermatologists over the last few years in canines with alopecia X. It has apparently been successful in approximately 53% of the cases. Therefore, in spite of this modest success rate, melatonin is a valuable therapeutic alternative to try because of its safety: being a 100% natural product, and low cost. It is been found that the hair growth observed in alopecic dogs treated with melatonin implants (Dermatonin) might be due to either modulation of sex hormone levels, action at the hair follicle level by blocking estrogen receptors (estrogen can inhibit anagen initiation) or actual melatonin deficiency. Also note Dermatonin can be used in conjunction with other drugs; i.e. lysodren, prednisone, anipryl, leuprolide and cimetidine.

Your Melatonin implants (Dermatonin) can provide a needed treatment for dogs that have Atypical Adrenal Disease. This is a condition with increased adrenal intermediate and sex steroid levels that gives you a variety of clinical presentations; one of them being the haircoat changes (or hair loss) referred to by veterinary dermatologists as Alopecia-X. There are also many dogs that have these hormonal changes that don't have haircoat changes, but one or more of the clinical signs usually associated with hyperadrenocorticism or Cushing's disease (liver changes {hepatomegaly, steroid hepatopathy, increased alkaline phosphatase and alanine aminotransferase enzyme levels}), polyuria and polydypsia, panting, etc. Though I don't have research data to prove the effectiveness of melatonin in these disorders (except in the one study done in ferrets several years back at the University of Wisconsin by Dr. Jan Ramer), many veterinarians do try melatonin in dogs with signs of Cushing's where cortisol is not increased, but rather adrenal intermediates (androstenedione, progesterone and17-hydroxyprogesterone) and sex hormones (estradiol), and subsequent adrenal steroid panels run through our Clinical Endocrinology Service shows that some of these hormone levels decrease when clinical signs improve.

Melatonin implants will prove superior to oral treatment with melatonin because of the bioavailability problems with oral administration, because of the loss of melatonin by "first pass" effect when melatonin is given orally, and because the drug is metabolized rapidly; thus, the probable need of a continuous release product for effectiveness. Elevated adrenal intermediate steroids, and sex steroids (mainly estradiol), give you all the clinical signs of dogs with the well-defined Cushing's disease syndrome.

The objective of this study was to assess the efficacy of a subcutaneous melatonin implant to suppress estrus in queens (felis catus). The hypothesis was that this implant would temporarily and reversibly suppress estrus in queens without producing any clinically detectable side effects. Fourteen adult queens were maintained in cages under artificial illumination (14 h light:10 h dark) for 45 d and then randomly assigned to one of two treatments. At interestrus, queens received a single subcutaneous melatonin implant (18 mg; Melovine [CEVA Sante Animal, Libourne, France]; MEL: n = 9), or a single subcutaneous placebo implant without melatonin (0 mg; PLA; n = 5). At the next estrus, all queens received a second MEL (n = 9) or PLA (n = 5) implant. Blood samples were taken when queens displayed estrous signs and during interestrus to measure estradiol (E2) and progesterone (P4), respectively, by radioimmunoassay. There were no significant differences in duration of the interestrus interval in PLA cats, regardless of whether the implants were placed during interestrus or estrus (6.0 ± 9.7 d vs. 6.0 ± 9.7 d, respectively; least square means [LSM] ± SEM). However, when MEL implants were placed during interestrus, the duration of interestrus was approximately twice as long as that occurring when MEL implants were placed during estrus (113.3 ± 6.1 d vs. 61.1 ± 6.8 d, respectively; P < 0.01). Serum E2 and P4 concentrations were similar in queens with PLA and MEL implants and in queens that received implants in estrus and interestrus. In conclusion, a subcutaneous MEL implant effectively and reversibly suppressed estrus in queens for approximately 2 to 4 mo with no clinically detectable side effects.

How do we treat Alopecia X?

As the name Castration-Responsive Alopecia implies, some dogs will regrow hair following neutering of the male dog or spaying of the female dog. Therefore, this is usually recommended first. You need to give the coat a few months to see if it will regrow before proceeding with other treatments.

Another treatment that works in about 30-40% of dogs is oral melatonin., a new product (Dermatonin) a melatonin implant is been shown to work in 60-70% of the treatment cases. This is a very safe treatment; however, it can affect a diabetic dog. Again, I can?t stress enough the importance of having your veterinarian first rule out any other diseases that can affect other systems before assuming your dog has Alopecia X.

THE UNIVERSITY OF TENNESSEE HORMONE PROFILE

One option in the pursuit effective Alopecia X therapy is the Adrenal Sex Hormone panel available at the University of Tennessee. This test is done by drawing a baseline blood panel, administering a pituitary hormone called ACTH, and drawing a second blood sample an hour later to compare. Samples are shipped to Tennessee for evaluation for numerous adrenal sex hormones. The results show not only what hormones respond abnormally but the university will make suggestions as to which therapy might be likely to work. Testing is not expensive and results only take a week to obtain so this will help in selecting what therapy makes sense to try next.

METHYLTESTOSTERONE THERAPY

Adverse Effects/Warnings-Melatonin in canines appears to be very safe.Use in breeding animals is questionable and may affect fertility and sex hormone secretion.In canines the use of subcutaneous implants/microchipshave been reported to cause site reactions in the form of a granulomatous sterile abscess containing lymphocytes, eosinophils and plasma cells. The abscesses are found in less than one percent (1%) of dogs administered the implant and is benign, however removal may be necessary. Please have your client maintain an evaluation of the implanted site.

PLEASE NOTE: Every effort has been made to ensure the accuracy of the information published. However, it remains the responsibility of the readers to familiarize themselves with the product information contained on the product label or package insert. To contact Melatek 877-635-2835.